Bottle-capping machine



Jan. 20, 1931. J rrr 5 AL 1,789,856

BOTTLE CAPPING MACHINE Filed June 15, 1925 5 Sheets-Sheet 1 ATTORNEYS Jan. 20, 1931. J. B. BABBITT ET AL BOTTLE CAPPING MACHINE 5 Sheets-Sheet 2 Filed June 15, 1926 3 w 4 W53? w V w w- Wflh 4 a w i! .w r 5 W W. w w J a W ATTORNEYS,

Jan. 20, 1931.

J. B. BABBITT ET AL BOTTLE CAPPING MACHINE Filed June 15, 1926 5 Sheets-Sheet 3 ATTORNEYS Jan. 20, 1931. J. BJ'BABBITTETAL BOTTLE curiae mourns Filed June 15, 1926 5 Sheets-Sheet 4 INVENTORS 7! ATTORN E-Y8 Jan. 20, 1931. J. B. BABBITT ET AL 1,789,856

BOTTLE CAPPING MACHINE 5 Sheets-Sheet 5 Filed June 15, 192.

ATTORNEYS away, taken inv the plane of the line YV of Fig; 2, looking in the direction of the Patented Jan. 20, 1931 UNITED STATES PATENT OFFICE f JAMEs'B. BABBITT, or YONKERS, NEW Yomgnivn oLIrFonn B; HARRIS, or WEE- HAWKEN, NEW JERSEY, ASSIGNORS, BY MESNE ASSIGNMENTS, T WALKER- eonnon LABORATORY ooMrAnY, me, or PLAINSBORO, new JERSEY, A CORPORA- TION or DELAWARE BOTTLE-CAPPING MACHINE Applicationfiied June 15, 1926; aria No. 116,153.

This invention relates to a machine for capping bottles and, more particularly, to a machine for spinning or drawing a thin metallic cap onto a bottle in order to seal the same. It is particularly adaptable to apply closures to milk and cream bottles.

An object of the invention is to provide means whereby a thin metallic cap that is slipped over themo'ut-h of a bottle may be sealed thereon'by a metal spinning oper-v ation as distinguished from a metal bending operation. I

Another object consists in providing means whereby the above named function may be automatically performed in a very rapid manner. p y

Another object consists in provid ng means whereby the above'named function may be performed without any movement of the bottle during the spinning operation.

Another object consists in providing means whereby the above named function may be performed on bottles of varying size and including normal irregularities, by the use-of the same apparatus.

A further object consists in providing certain improvements in the form, construction and arrangement of the several parts, whereby the above named and other objects may be effectively attained.

A practical embodiment of th'einvention is represented in the accompanying drawings, in which 7 Fig; 1 represents a side elevation of the apparatus, partly broken away,

Fig. 2 represents a broken longitudinal section, through the apparatus, partly in elevation, I

Fig. 3 represents a detail section, partly in elevation, of the lower portion. of the apparatus, with the, parts in position different from the position shown in Fig. 2-,

Fig. 4 represents an inverted plan view of the apparatus, y

Fig. 5 represents av section, partly broken arrows, V

-Fig-. 6 represents as milar v ew taken in to the contents and'also" the plane of the line VI-Vl of Fig. 2, looking in the direction of the arrows,

Fig. 7 represents a detail section, partly in elevation, showing certain actuating parts in one position,

Fig. 8 represents a similar view showing said parts in another position, i Fig. 9 representsa detail elevation showing, a cap or closure loosely placed on bottle, and

Fig. 10 represents a similar view showing the cap or closure after it has been spun on the bottle.

As is known, milk and cream bottles are commonly closed-with a pasteboard disk that'fits against the shoulder within the mouth of the bottle. This is commonly called a pulp cap. i

It is desirable that some means should be provided for additionally sealing the said bottles in order to provi better protection 1 order to hinder counterfeiting or substitution. a metal cap welllends itself but, to our knowledge, theonly such cap that has been previously used is com-posed of lead. This has numerous disadvantages, because it tends to tarnish, the print thereon tends to become illegible, and the soft, yielding nature of the metal enables the cap to bQl'GlllOVBti and replaced so as to facilitate substitution or aduiteration.

. By our invention, We are able to. apply a cap of thin, comparatively hard material, such as aluminum, in such a wavthat it cannot be removed from the bottle without destroying it and thereby preventing its replacement. This metal, furthermore, does not noticeably tarnish and well retains the lettering applied thereto. i l

The machine or apparatus embodies a drum 1 that isembraoed by a fork 2 which has its arms provided with inwardly projecting lugs 3 that enter slots 4 formed in the sides of the drum. and one slot, are shown, but it willbe und'crstood that corresponding, oppositely dis posed, parts are provided Y The fork 2 is pivoted at 5 in bracket 6 which is suitably secured to .anyconvenient Only one arm, one lug, 9

To this end support so as to suspend the capping apparatus in such position that bottles may be fed beneath it.

A rearward extension 7 is provided on the fork 2 and it has a pivotal connection 8 with a rod 9 that extends downwardly to suitable mechanism, such as a cam device, (not shown) for periodically reciprocating the rod 9 and thereby reciprocatin the capping apparatus in order to bring it down upon and lift it away from each bottle as it is placed beneath. Such cam mechanism for raising and lowering the capping apparatus is conventional and so well understood in this art that it is not deemed necessary to illustrate the same.

The upper part of the drum 1 has an interior annular flange 10 which is angular in cross section so as to rest upon the top of the drum, in 'which position it is suitably fixed, as by screws. 7

1V ithin the said flange 10* is located a hollow spindle 11 that is exteriorly threaded to receive a nut 12 which rests upon an antifriction bearing 13 that is interposed between the nut 12 and the flange 10. In this way, the spindle is prevented from downward movement in the drum 1.

At a point below the flange 10 the spindle has a shoulder 14 a 'ainst which a collar 15 abuts, and a thrust bearing 16 is interposed between the said collar and the flange 10. These parts prevent upward movement of the spindle 11 in the drum 1.

Below the parts just described, the drum has another inner annular flange 17, and the spindle 11 has another nut- 18 threaded thereupon. An anti-friction bearing 19 is inter posed between the flange 1? and nu; 13. The spindle also has another shoulder 20 iitted to receive a thrust bearing 21 that is interposed between it and the flange 17.

These elements just described provide ad ditional support against upward and downward movement of the spindle 11 within tlr drum 1. Rigidity in this respect, together with the provision of su'l flcient thrust bearings, is desirable because of the substantial and repeated strains put upon the apparatus in the capping operation.

A suitable oil retaining washer 22, of felt or like material, is fitted around the shoulder 20 and rests upon a flange 23 that projects laterally outwardly from the spindle 11.

A head 24: is threaded to the lower of the spindle 1;, and to it is secnren, as by a set of screws 25, a ring 26 that embiaces and is fixed to a cylinder 27.

The ring 26 has an outwardly projecting flange 28 in which is mounted a series of )ushings 29 that rotatably receive a series of shafts 30. Six of these shafts are shown in the present embodiment.

The lower part of the cylinder 2'? has-a similar flange 31 in which is mounted a series of similar bushings 32 that receive the lower portions of the shafts 30.

Collars 33 are pinned to the shafts and rests upon the bushings 32, so as to prevent downward movement of the shafts in the flanges 28 and 31.

The upper ends of the shafts 3O carry pinions 35, that are pinned thereto, one on each shaft. The said pinions surrounded and meshwith a ring gear 3} that has an upper enlarged portion 3. which overlies the pinions, whereby the ring gear is supported in position.

The upper end of the spindle 11 has a bevel gear 38 fixed. thereto, as by a set screw 39, and said gear meshes with a corresponding gear 40 that is lined by a screw 41 to the shaft l2 of a motor 13 that is mounted on a suit-able bracket, or other support, 44.

This provides a source of power for rotating the spindle 11, and the latter is rotated at high speed during the operation of the capping apparatus.

The rotation of the spindle carries the shafts 30 bodily around with it, so that they revolve about the spindle, and the meshing of the pinions 35 with the ring gear 36 causes the latter to rotate about its own axis, but does not normally cause any rotation of the pinions 35 about their own axes.

A rod 45 has its upper end loosely travers ing a bored arm 16 which is carried on a standard a? that is supported on a bracket 4E8.

Another arm -19 has one end embracing and lined to the rod l5 by a screw 50. The opposite end of the arm 49 slidably engages the standard 17. An expansion coilspring 51 surrounds the rod 45 and is interposed between the arms 1-6 and 49, thereby normally urging the rod in-a downward direction.

The lower end of the rod 15 is threaded, and this is made a left hand thread in order to prevent the parts carried thereby from loosening in operation.

On the said thread is fitted a thimble 52, and above the thimble a sleeve 53 is rotatably n'iounted on the rod l5.

A dome 5a is fined on said sleeve immediately above the thimble. The said dome has an inwardly extending annular flange 55. An anti-friction bearing 56 is located between said fiange and a flange 57 on thimble The dome is made in two parts, as'indirated in the drawing, (F 1g. 2) in order to permit the insertion of the said bearing, the

said parts being held together by screws The lower part of the thimble 52 is reduced in diameter, and there is mounted on it a chuck 58, which chuck is clamped between ashoulder formed at the top ofthe reduced portion of'the thimble and a nut 59 that is screwed onto the end of the rod 45. An anti friction bearing 60 is located between the top of the chuck 58 and theunder side of the flange 55.

'An expansion and torsion sping 61 surrounds the sleeve 53 and has one end fixed there above so as to accommodate nuts 65', 66

and 67. Nut 65 bears on the top of plate 63 so asto limit its upward movement under the influence of spring 61, and nuts 66 and 6 serve as lock nuts to prevent the parts from moving under vibration engendered in operation.

A pin- 68 is carried. by and projectsdownwa-rdly from the head I t entersa curred slot 69 (Fig. 6') formed in the plate 63 in order to limit the turning movement of said plate under the torque of, spring 61. The said spring causes the pin 68- normally to remain in abutment with one end. of slot 69, as shown in Fig. 6.

An angular member 7 O has one portion set into and lined to the top of plate 63 by a screw 71:, and itsother portion depends from the edge of-the said plate, the said depending portion being beveled, as clearly shown in Figs. 7 and 8, inv order to PI'OXlQlQ a cam sur-- face.

A shell 72=surrounds the dome 54- and rests upon ashoulder '13 formed at the lowerpart of said dome. This shell is fixed to the dome 1 by screws 74, andit carries, near its top, a

set screw 75,- the head of which is fitted to ride in a vertical slot 'Zdfashioned in thesi-d'e ot' the cylinder 27. Theengagementbetween the head of the screw 75 and the slot 76 eanses the shell 72', and the parts f'aast thereto,.to turn with the cylinder 27, and said engagement also limits the downward movement of the rod 45 and parts carried thereby since said movement terminated by contact of the screw 7 5 with the bottom of. slot 76.

The shell 7 2 has a notch 77 formed in its upper edge, as clearly shown in Figs. 7 and 8, and said notch has a beveled side adapted to mate with the bevel on the cam 70in. order that relative axial movement of the shell 7 2 and cam 70 may impart a slight rotary movement to the plate 63.

A set of pins 78, three beingshown in the present instance, is loosely carried in holes formed in movement of the plate in a rotary directionund'er theinfluence ot spring- 61 so as, to

the head 24, and each pin has anenlarged head 79 that prevents it from falling The plate 63 hasbring the pin 68'into abutment with the other end of slot 69, opposite to the position shown in Fig. 6,.will make: the pins 78 and holes 80 coincide, sot-hat the pins may enter the holes 80 if the plate63 is raised or the pins lowered.

The lower extremity of each shaft 30' has a collar 81 fixed thereto immediately below the flange 31. A disk 82,,oi'ifriction material? such as rubliier, surroui'llds the shaft and abuts theundersideof the collar 81. A thin washer 83, which may suitably be composed of copper, surrounds the shaft 30 and abi'its the .lower'face of the friction disk 82. A hub 84 is rotatab-ly mounted on the sh aft 30 immediately bel'owfthe washer 83, and a nut is threaded on the end of the shaft to clamp the elements 82; 83 and 8 1 between itself and the collar 81. It will be understood that each one of the six shafts 30 is equipped with. the .iarts just. described, and that the result of this arrangement is that eachhub 8 2 will be irictionally driven to rotate it its shaft 3O'is rotated.

Each. hub 84 has a hole formed in one side thereof, as. clearly shown in Fi g. l, and each hole receives the buttof a wiper or spinning element 86, which is mounted: at an angle to the horizontal. Thesaid wipers are substanr tia'lly square. in cross section, and each one is clamped. in the hole in its hub 8% by a set screw 87. The wipers operate with their edges and it will be seen that, when an edge becomes dull, the said screw 81 may be loosened and the wiper turned ninety degrees so as to present a fresh edge to the work, after which the screw 87 may again be tightened.

The-free end of each wiper owerlaps and liesabove thebutt of an adjacent wiper,and each hub 84 is cut away, as clearly shown in 2, in order to give additionalfreedom of movement to the free en dot the wiper carried by the adjacent hub. a

The wipers or spinning elements 86 are mounted inthe hubs 8 1 so that thebutts of three. alternating wipers lie' in the same horizontal plane. The butts of the other three wiper-s also lie in; a single'horizontal plane, but the said two planes are different. In other words, the butts of three alternating; horizontal] wipers lie in a plane above the plane in which the buttsco't the other three alternating wipers lie. Each wiper projects upwardly from its butt to its free end at the same angle,.sothat the free enes of three alternating wipers lie in a plane abovetheplane in which the free ends of the other three alternating wiperslie. 5

The arrangement. just described promotes the'drawing operationiot the wipers orspinninni elements during the operation of seal..- ing: the caponto'thebottle.

The drum 1? has, at itsbase, a jecting circular flange 88 which is provided laterally 1 i with a recess in'its lower face that 'receivesan annular. friction. element- 89 which; may be composed of leather, or other suitable material. The said elementis adapted toofrietionally contact with flange 37 on ring gear 36 at certain periods during the operation of the apparatus, as will be hereinafter described.

A bottle is represented by 90 (Fig.9) and a cap prior to the spinning operation is marked 91. Such a cap may he formed by a drawing operation from thin sheet material, such aluminum, and it is preferably made slightly larger in diameter. at its open end thanatits closed end, in order to facilitate placing the caps rapidly upon the bottles.

Fig. 10 shows the cap after it has been spun onto the bottle for sealing engagen'ient therewith.

In operationithe spindle 11 is normally driven at conmaratively high speed by the motor -l3. This rotation of the spindle, also rotates the cylinder :27 and it bod iy carries the shafts 30 so that they revolve in a path about the axis of the spindle. This revolution causes the pinions 85 carried by the shafts 30, to rotate ring gear 36 about its axis.

Bottles are brought, in sequence,to a position underneath the apparatus, as by suitable conveying means (not shown) which is well understood in the bottle caping industry. Each bottle in gripped to prevent its rotation at the time the cap is being spun thereon, and such automatically operating gripping mechanism is also well known in this industry and is not therefore, shown or described, as its particular form constitutes no part of this invention.

After a bot-tie, with a cap loosely mounted thereon, as shown in Fig. 9, has been brought beneath the capping apparatus and gripped, the said apparatus is moved down, as a whole, upon the bottle, by the fork 2 which is actuated by the rod S) hereinabove described. it will be understood that the mechanism actuating the rod 9 timed so as to periodically depress the e pping apparatus as each bottle is gripped in position there-beneath.

As the capping apparatus moves downwardly, the cap resting on the upper end of the bottle comes in contact with the chuck 58 and prevents it and associated parts from further downward movement. This stops the downward movement of the rod l5, dome 5 and shell 72, but, owing to the elongated slot 76, it does not stop the continued downward movement of the cylinder 27 and associated parts.

The continued downward movement brings 5 the slate 63 nearer to the underside of the head 24, which latter moves with the cyhnde'r 27, and this causes the pins 78 to be relatively elevated and come into contact with the uncerside of ring gear 36, thereby preventing its downward movement and causing the friction elements 89 to come into contact with its upper surface. I F I This contact between flange 31 on ring gear 36 and frictionelement 89 retards or stops the rotation of the ring gear end, since shafts 30 continue their revolution, the pinions 35 thereon are-rotated by their engagementwith the ring gear 36, and thereby rapidly rotate the shafts 30.

This rotation of the shafts 30 at once swings the wipersor spinning elements into contact with the sides of the cap on the bottle. When such contact is firmly made, the frietionally engaged elements 82, 8S and 84 begin to s ip'so that, while the shafts 30 continue their rotation, the hubs 84L merely tend to 1'0- tate so as to retain the wipers So in firm contact with the cap on the bottle.

This condition of the parts, together with the continued downward movement of those portions of the apparatus which carry the w pers, causes the cap to be spun tightly about the bottle, into the condition shown in F 10. This is a metal spinning and metal drawing operation which, in effect, causes minute puckers in the free portion of the cap and progressively irons out the said puckers so as to deform the metal of the cap to the shape shown in Fig. 10. It will be understood that the tendency of the hubs 8% to rotate will cause the wipers to maintain firm contact with the decreasing diameter of the cap as the apparatus moves downwart ly. and this frictional yielding mounting of the wipers enables them to adapt themselves to irregularities in the bottle, and to varying sizes. i

As each succeeding wiper is mounted in a different plane from the preceding one, and as all are mounted at an angle to the hori- Zontal, t l e spinning or drawing operation is effectively attained.

As the spinning of the cap nears its completion, the cam surface of notch '77 comes into contact with the cam surface because the abutment of pins 78 with ring gear 36 and the abutment of the latter with friction element 89, prevents further relative upward movement of plate 63. This causes spring 31 to be compressed by the continued relative upward movement of the dome 54-, thus bringing the said cam surfaces into contact, as stated. As this movement continues, the effect of the said cam surfaces is to slightly turn plate (52) against the torque of spring 61 and thereby move it in such direction as to bring pin 68 toward the end of slot 69 opposite to that engaged by pin (58' as shown in Fig. 6. This turning movement of plate 63 graduallymoves pins 78 toward holes 80 and, when the spinning operation is completed on the cap, the said pins 78 come into register 'th and enter holes 80. This brings about disc ement between flange 37 on ring gear 36 and friction element 89, thereby permitting the ring gear to again start rotating about its axis under the influence of the revolving pinions 35, which pinions simultaneously cease rotating about their own axes. This cessation of rotation of said pinions releases the tendency of the hubs 84 to rotate and thereby releases the pressure of the wipers against the cap. At this juncture centrifugal force throws the wipers in the opposite direction from that in which they have been previously urged, so that they clear the cap.

i The actuation of the rod 9 is now such as I vto hft the entire apparatus, by means of the fork 2, and the cap spinning operation has been completed, so that the capped bottle may be passed on and replaced by another. This upward movement releases the pressure of the chuck58 on the cap and bottle, and thereby enables spring 61 to force dome 5a and plate (SS-apart so. that cams and 77 are-disengaged, Ihecontinu-anceof the movement lifts the cylinder 27 relatively with respect to shell. 72 until screw 75 abuts the bottom of slot 76. This, of course, pulls the pins 7 8 out of the holes and, as soon as they are clear of the said holes the torque ofspring 1 turns plate 63 back into the position shown in Fig. 6, so that pins 78 no longer coincide with holes 80.

In actual operation the work is very fast, and we have found it satisfactory to rotate the spindlell at aboutlSOO B. P. M., so that the shafts 3O rotate at about 3600 R. P. M.

Each period of rotation of the shafts 30 is,

of course, very brief, as each cap is spun down in an exceedingly shortperiod of time.

. We desire it to be understood that various changes may be resorted to in the form, construction and arrangement of the several parts, without departing from the spirit and scope of our invention; and hence, we do not intend to be limited to the details herein included in the claims.

Vhat we claim is:

1. Apparatus of the character described comprising, rotating means, revolving means actuated by the rotating means, said revolving means being rotatable, a second rotat ing means actuated by the revolving means, means for hindering the rotation of said second means in order to cause it to rotate the IGVOlViIlg' means, and means operable by enshowu and described except as they may be gagement of the apparatus with the bottleee r i e, a single spinning element earned by each intooperation, and spinning elements operated by the revolving means.

3. Apparatus of the character described revoluble and rotatable means,

said means, and adapted for simultaneous operation upon the cap to be applied and a slip connection between said elements and said means whereby the elements can revolve without rotating while the means is revolving and rotating. I V

4. Apparatus of the character described comprising, a revoluble spinning element, means for urging said element inwardly into contact with a cap on a bottle, and means for interrupting said urging means, said spinning elementbeing adapted to be moved by centrifugal force out of contact with the cap when the urging means is interrupted.

, Apparatus of the character described" compr1s1ng,a serles of revoluble spinning elements, means for urging said elements inwardly into contact with cap one bottle, and means for lnterrupting said urging means, said spinning element being adapted to be moved by centrifugal force out of con:

tact with thezcap when the urging means interrupted. V

6. Apparatus of the character described comprising, a series of revoluble spinning elements adapted to be normally urged away from-operative position by centrifugal force, and intermittently actuated slip drivezmech anism for urging them into operative-position. c

V 7. Apparatus of the character described comprising, a series of revoluble spinning elements adapted to be normally urged away from operative p'osition by centrifugal force, intermittently actuated slip drive mechanism for urging them into operative position, and means operable by engagement of the apparatus with the bottle to be capped for controlling said slip drive mechanism.

8. Apparatus of the character described comprising, a spinning element, means for urging it into contact with a cap on a bottle, and mechanism for interrupting said urging means, said mechanism including two members adapted for relative axial movement with respect to each other, means for causing said relative axial movement to impart to one of said. members movement in a rotary direction.

9. Apparatus of the character described comprising, a spinning element, means for urging it into contact with a cap on a bottle, mechanism for interrupting said urging means, saidmechanism including two members adapted for relative axial movement withrespect to each other, means for causing said relative axial movement to impart to one of said members movement in a rotary direction, and intermittently actuated means for causing said relative axial movement,

rection, intermittently actuated means forcausing said relative axial movement, andmeans for reversing said relative axial movement.

11. Apparatus of the character described comprising, a spinning element, means for urging it into contact witha cap on a bottle, mechanism for interrupting said urging means, said mechanism including two mem bers adapted for relative axial movement with respect to each other, means for causing said relative axial movement to impart to one of said members movement in a rotary direction, intermittently actuated means for causing said relative axial movement, means for reversing said relative. axial movement, and means for reversing said movement of said member in a rotary direction when said relative axial movement is reversed.

12. Apparatus of the character described comprising, a series of spinning elements, means for urging them into contact with 'a cap on a bottle, and mechanism for interrupting said urging means, said mechanism including two members adapted for relative axial movement with respect to each other, and means for causing said relative axial movement to impart to one of said members movement in a rotary direction.

1?). Apparatus of the character described comprising, a series of spinning elements, means for urging them into contact With a cap on a bottle, mechanism for interrupting said urging means, said mechanism includ-' mg two members adapted for relative axial movement with respect to each other, means for causing said relative axial movement to .impart to one of said members movement in a rotary direction, and intermittently act-ua'ted means for causing said relative axial movement.

ll. Apparatus of the character described comprising, a series of spinning elements, means for urging them into contact with a cap on a bottle, mechanism for interrupting said urging means, said mechanism including two members adapted for relative axial movement with respect to each other, means for causing said relative axial movement to impart to one of said members movement in a rotar direction, intermittently actuated means for causing said relative axial movement, and means for reversin said relative axial movement.

15. Apparatus of the character described comprising, a series of spinning elements,

means for urging them into contact with a cap on a bottle, mechanism for interrupting said urging means, said mechanism including two members adapted for relative axial movement with respect to each other, means for causing said relative axial movement to impart to one of said members movement in a rotary direction, intermittently actuated means for causing said relative axial movement, means for reversing said relative axial movement, and means for reversing said movement of said member in a rotary direction when said relative axial movement is reversed.

16. 111 apparatus of the character described, a series of spinning elements, said elements being in the form of substantially rigid fingers movably mounted at an angle to the horizontal, certain of said. elements being in a different plane from others.

17. In apparatus of the character described, a series of spinning elements, said elements being in the form of substantially rigid fingers movably mounted at an angle to the horizontal, adjacent elements being in different planes and alternating elements being in the same plane.

18. In apparatus of the character described, a spinning element in the form of a finger, said element having an angular cross section, and means for adjusting the mount ing of said finger so as to present different edges to the work.

19. Apparatus of the character described comprising, a rotating spinning element support, a series of shafts revolved thereby, a separate rotatable element operatively connected to said shafts, a friction surface, and intermittently actuated means for moving the separate element vertically into and out of engagement with the friction surface for alternately causing and arresting rotation of the shafts. 7

20. In apparatus of the character described, a series of spinning elements, adjacent elements being in different horizontal planes and alternating elements being in the same plane, and a series of hubs for supporting the spinning elements, said hubs being cut away to give increased freedom of movement to the free end of the spinning clement supported by the adjacent hub.

In testimony, that we claim the foregoing as our joint invention, we have signed our names this 17th day of May, 1926, and this 29th day of May, 1926.

JAMES B. BABBITT. CLIFFORD B. HARRIS. 

